Magneto–rheological (MR) dampers are semi–active devices in vehicle suspension systems that pro–duce controllable forces dependent on the input current to the damper as well as the relative velocity of the sprung mass. In this paper, by the response prediction of nonlinear quarter–car model which in–cludes a nonlinear MR damper dynamics, a new optimal tracking controller is analytically designed for the semi–active suspension system. In order to develop a more accurate control law, a realistic nonlinear model of the spring force is also employed in the design model. In the proposed scheme, the control input is the input current to the MR damper and is determined by minimizing a pointwise per–formance index defined as a weighted combination of ride quality and control energy. Optimal prop–erty of the control law provides the possibility of limiting the input current to the MR damper, as the control input, to the physically admissible range. The performed analysis and the simulation results indicate that the proposed non–linear controller can improve the vehicle ride comfort using the re–duced input current to the MR damper without deteriorating the handling performance.

Design of modern car suspension systems with contradictory limitations on ride comfort and handling is a challenging task. In this paper, Application of different control methods and effect of combining these methods on semi–active suspension systems...

Semi–active structural control for improving the structure’s performance against the external excitations, mainly wind and earthquake, has received remarkable attention recently. Among different methods of implementing smart control in structures,...

Thispaper, for the first time, reports a mathematical formulation and numerical simulation of the effect of crystallinity on cell growth in semi–crystalline microcellular foams by solid state batch foaming process at high temperature. Well–known Cell...

This paper presents multi objective genetic algorithm optimization response control of a 3D 9–storey building frame using MR damper Equations of motion for thestructure equipped . quipped with MR dampers have been established Three approprate...

In this paper, the effect of tire normal force control on the anti–lock braking system (ABS) performance is studied through the integration of suspension and braking control systems. The ABS performance in generating the maximum braking force is...

In this paper, an adaptive fuzzy controller is synthesized to improve the anti–lock braking system (ABS) performance in the presence of suspension systemeffects. The ABS performance in generating the maximum braking force is mainly affected by the tire normal force applied the suspension system. In thisstudy, an optimization is carried out to obtain the optimal value of longitudinal slip reference value corresponding to the suspension normal force andvehicle speed. The slip optimal value is then imported as the reference input of the fuzzy controller. In this manner, the fuzzy controller is adapted to the tirenormal force, suspension deflection and vehicle speed. Therefore, this controller is aimed at tracking the slip optimal value which is updated by on–line data from suspension system and braking system states. In this study, two quarter car models are used to simulate the ABS and suspension systems behavior.The first being a quarter car suspension model with two degrees of freedom which describes the sprung and unsprung mass vertical dynamic and the latter a quarter car braking model with two degrees of freedom which describe the braking dynamics (vehicle longitudinal dynamic). Simulation of this study is derived during hard braking on a poor quality white noise road. The stopping distance is compared in the cases of fuzzy and adaptive fuzzy ABS control situations while a passive suspension is employed. The results show that the adaptive fuzzy control strategy can be helpful to increase the ABS controller performance so that it decreases the stopping distance in the semi–real situation.

Saffron (Crocus sativus L.) from ancient times has been used as medicinal herbolary Saffron, rich sources of carotenoids, is known for its anti–cancer and anti–tumor effects. It was known that estimated chemical composition and concentrations of main...

The huge wide–spread changes resulted from globalization, in particular the globalization of economy, the revolution of ICT technologies and the hegemony of critical social theory affecting the countries’ economic and legal policy making process,...

This study presents control of inverted pendulum via on–line fuzzy backstepping and anti–control of chaos. The inverted pendulum, as a mechatronics system, is usedfrequently in robotic applications and can be found in different forms. Based on...

In this paper, the effect of tire normal force control on the anti–lock braking system (ABS) performance is studied through the integration of suspension and braking control systems. The ABS performance in generating the maximum braking force is...

Development and utilization of Low Dosage Hydrate Inhibitors (LDHI) have been attracted researchers and industry for almost two decades. These inhibitors are known to be more effective, more environmental friendly, less corrosive and havelower...